The clubs are part of a movement encouraging adults to indulge their interest in and fascination with elaborate designs, robotic spectacles and train systems made with Lego elements.

"What attracts me is the building," says Brian Alano, 35, of Bloomington, a member of IndyLUG, a 6-month-old Indianapolis chapter. "I don't build things and put them on the shelf and look at them. I build them and take them apart."

"LUG" refers to Lego User Group and there are Web sites, message boards, news groups, public displays, Guinness Book of World Records challenges and software programs to satisfy every degree of addiction.

Lego, a privately held Danish company, started in 1932 as a maker of wooden toys.

Getting on the Star Wars bandwagon and introducing the Mindstorms robotics line in the 1990s caught the attention of many adults who thought they had left Lego bricks behind.

Growing market

Adult Lego play is big business. One company, Bricklink.com, traffics exclusively in Lego pieces. It has nearly 8 million for sale by the pound, odd lot, complete set and individual premium vintage piece.

Enthusiasts fall into two camps: those who never lost interest and those who stowed the bricks away, only to find themselves lured back.

There's even a name for the Legoless years - "the Dark Ages."

Leah Cardaci, 21, a college computer major, has been a Lego aficionado since she was 12 and estimates her collection to be in the 40,000-piece range.

She ran across information about the Indianapolis chapter on the International Lego Users Group Network Web site, www.Lugnet.com.

Different priorities

Adults clubs aren't a surprise to Lego executives. Jake McKee, 28, is the corporate guy in touch with adult clubs around the country.

Each club is different, McKee says. Some are focused on design and construction, some are more into socializing, and others are drawn together because no one member has enough bricks to build something spectacular.

Most of the clubs are similar. Members tend to be male, age 35 or younger, and involved in computers or high-tech jobs.

Cardaci has no problem being the only female member of her chapter. "The main thing is, we are interested in the Lego," she says. "That's enough to make you feel welcome in the group."

Membership is open to anyone 18 and older. Steve Martin, 33 of Noblesville, Ind., who has about 100,000 pieces, says organizing a Lego collection can be a challenge.

"The more you have, the more elaborate storage generally gets."

Like many LUG members, Martin has kids with Lego sets of their own. The house rule is simple: The collections never mix.